The JetBrains 2019.2 IDEs include first-class support for TextMate bundles:
Right now if you configure the base IDE to make this work, you lose syntax highlighting for JS/CSS in
style blocks in markup files. This is because you have to remove the file type associations for
*.css and allow the TextMate Bundles plugin to do the work of syntax highlighting.
When IC runs in a 2019.2+ CE base IDE, it should prompt the user to use TextMate Bundles for syntax highlight similar to how it does now for extended CSS syntax highlighting, and it should also use the TextMate Bundles plugin to provide syntax highlighting for those languages embedded in markup.